Democrats are replaying one of their greatest hits of 2012 in their furious battle to minimize their midterm losses in a political environment defined by an unpopular president and general unease.

And why not? The war on women has a proven record of success — in mobilizing Democratic women and trumping what would otherwise seem much more important issues — and it is so simple that any idiot can run on it.

The recipe is one part taking offense where clearly none was intended, and one part discerning new nefarious schemes to deny women access to birth control.

If War on Women 1.0 was strained and unconvincing, the new version lacks all self-respect. To paraphrase Karl Marx, it is history repeating itself, first as farce, then as self-parody.

Every word spoken by a Republican is mined for its latent sexism.

When a spokesman for the National Republican Senatorial Committee last year called Alison Lundergan Grimes, the Democratic Senate candidate in Kentucky, an “empty dress,” it seemed an innocuous play on words — unless you were familiar with the insidiously subtle ways Republicans wage their war on women.

A Grimes spokesman called the comment offensive, degrading and appalling, and then must have run out of adjectives. A spokeswoman for the Democratic Senatorial Campaign Committee, Regan Page, found the remark “despicably offensive.” Grimes integrated the remark into her stump speech.

During their first debate in North Carolina, Republican candidate Thom Tillis referred to Sen. Kay Hagan by her first name, offending her supporters with his undue familiarity. He compounded the sin by saying Hagan’s “math just doesn’t add up,” a hoary cliché in politics for decades.

Hagan pronounced herself (what else?) “insulted,” and Page brought out more of her double-barreled plaints. She accused Tillis of “ugly condescension,” “outrageous mansplaining” and “condescending patronization,” which is always to be distinguished from “patronizing condescension.”

It’s as if the faculty of the women’s and gender-studies department at Wellesley runs the Democratic Party. The assumption is that women are strong and independent — just don’t say the wrong word around them or they will get the vapors.

This is all so silly that it is especially off-key in current circumstances. The implied Democratic message is that, yes, the president is broadly unpopular, the economy is middling and the world is falling apart — but someone called me “ma’am”!

To the extent that the war on women has any substance, it centers on minor but flawed pieces of federal legislation like the Violence Against Women Act and the Equal Pay Act. And contraception. Always contraception.

The Democrats deserve credit for managing to portray a position supported by no one serious in public life — that women should be denied birth control — as the default position of the Republican Party.

The Colorado Senate race has been so focused on abortion and contraception, it could be mistaken for a leadership election of the American College of Obstetricians and Gynecologists.

Playing defense, Republican Cory Gardner is one of a handful of GOP candidates who have come out in favor of over-the-counter birth control.

It is a testament to the endless malleability of the war on women that this innocuous proposal to provide more ready access to birth control is itself taken as a dastardly plot against women.

The wonder of the war on women is that it works, or at least it has. Republicans have a better chance of deflecting it this year.

They have more deft candidates, and while the over-the-counter contraception proposal is small beer, it is a compelling way to demonstrate comfort with the very access to contraception that Democrats allege Republicans want to take away.

More importantly, the Republican Party should realize that its fate with all voters depends on having a concrete agenda to address the nation’s challenges here and abroad. That is the ultimate insulation from the insipid politics of the ever-more-tenuous war on women.